Sativa = Head high
Indica = body stone

One isn't necessarily "higher grade" than the other just different effects, though most people find the effects of sativa a bit more enjoyable most of the time.

Eating from my experience leads to the same effects only the timing is different. It takes 1 - 2 hours for onset and lasts anywhere from 4 - 8 hours. Paranoia isn't necessarily more prominent, but proper dosage is much harder, since it takes so long for the effects to kick in. Often too large a dose can cause paranoia with inexperienced (or otherwise paranoid) users.

Hope this helps!